Quran, Chapter 16, Verse 94:
and do not make your oaths a means of deceit between youIn some verses of Quran, God almighty swears by different things to emphasize the importance of the topic. In one case, god almighty swears by the location of the stars and right after emphasizes on the importance of this oath. This is mentioned in the following verses:

Quran, Chapter 56, Verse 75-79:
I swear by the falling of stars, and most surely it is a very great oath if you only knew, most surely it is an honored quran, in a book that is protected, none shall touch it save the purified ones.In order to grasp the importance of this oath, one should know something about our immensely vast universe with its billions of galaxies and stars. Only in our galaxy there are about 500 billion stars. All of these stars move in a fixed orbit around the center of the galaxy. Considering these many stars moving with different speeds , it is very rare that two stars collide with each other. Swearing by the stars is also repeated in other verses of Quran:

Quran, Chapter 86, Verses 1-4:
I swear by the heaven and the comer by night, and what will make you know what the comer by night is? the star of piercing brightness; there is not a soul but over it is a keeper.

Quran, Chapter 53, Verses 1-4:
i swear by the star when it goes down, your companion does not err, nor does he go astray; nor does he speak out of desire, it is naught but revelation that is revealed.

Quran, Chapter 81, Verses 15-19:
but nay! I swear by the stars, that run their course (and) hide themselves, and the night when it departs, and the morning when it brightens, most surely it is the word of an honored messenger